Category: Biology Second Paper Lecture Sheet

1. It is a gametophytic (haploid) plant.
2. Its body is thalloid i.e. the body cannot be divided into roots, stems and leaves.
3. Its thallus is green, recumbent, hemispherical and flattened. Dr. Siddique Publications
4. The thallus is bifurcated and each branch has a groove at the head.
5. The lower surface of the thallus consists of unicellular smooth and irregular rhizoids and multicellular scales.
6. The upper part of the thallus is green and capable of photosynthesis and the lower part is colorless and storage zone.
7. The accumulation zone is colorless, composed of parenchyma cells and without air chambers.
8. The photosynthetic zone consists of air chambers and the chambers are directly exposed to the air. Dr. Siddique Publications
9. They are homosporous. ie produce identical spores.
10. Spores are released as a result of decay of the thallus.
11. The female genitalia is an archegonium and is fluted or pitcher-shaped in appearance.
12. The stamens are the antheridium and appear pear-shaped, round, oval or cylindrical.
13. The sporophyte is dependent on the gametophyte.
14. They reproduce asexually and sexually.

Kingdom : Plantae
Division : Bryophyta
Class: Hepaticae
Order: Marchantiales
Family : Ricciaceae
Genus : Riccia

Riccia is found in almost all countries of the world. They are born in clusters in round clusters during monsoons. They grow on moist or damp soil and moist walls. The only species Riccia fluitans grows floating in water. Various species of Riccia grow in mountainous regions including Sylhet, Bangladesh.

A genus in the class Hepatica is Riccia. Worldwide it is known as moss. Their common name is liverwort. The genus Riccia has about 200 species. 45 species of this genus have been identified in Bangladesh. Some of the species found in Bangladesh are Riccia chittagogensis, Riccia dhakensis, Riccia gangeticus, Riccia discolor, Riccia amelli, Riccia crystallina, Riccia personii etc.

Bryophyta grow in terrestrial or moist terrestrial environments. They absorb water like aquatic plants. They need water for reproduction, growth and development. Like aquatic plants, they have stomata. During sexual reproduction, their sperm swim to the egg and fertilize it in the presence of water. That is, water is essential for their life cycle. Hence bryophytes are called amphibious plants.

(i) They are known as mosses.
(ii) Their gametophytes are cylindrical or thallus shaped and develop into protonema.
(iii) Their body is more like a stem and the genitalia are formed at the tip of the stem.
(iv) Their sporophytes are divided into pods, setae and capsules.
Examples: Funaria, Sphagnum, Pogonatum.

Hornworts are hornworts in which the sexual structure of mosses or gametophytes is horn-shaped.
(i) Their main plants are gametophytes. It is green and flat in structure.
(ii) Their sporophytes are partially self-sustaining.
(iii) They are developed and have columnar capsules.
(iv) Their thallus is heterolateral and recumbent. The genitalia are rooted on the surface of the thallus.
(v) They are found all over the world. Their number of species is 300.
Some hornworts- Anthoceros agrestis, Phaeoceros carolinianus, Ceratophyllum pollination, Folioceros amboinensis, Dendroceros crispus, Notothylas anaporata.

Liverworts or liver plants are those moss-like plants or gametophytes with liver-shaped leaves.
(i) They are gametophytic plants. The body is thallus in nature.
(ii) Their genitalia are located on the surface of the thallus. Pungdhani is pear shaped and stridhani is flask shaped.
(iii) They are small independent plants. Less than 10 cm in length and 2-20 mm in width.
(iv) They are widespread all over the world. It has 6,000 species in polar, desert and humid regions.
(v) They grow on soil, sand, stone, tree or any object.
A few liverworts- Riccia huebeneriana, Marchantia polymoroha, Asterella californica, Ricciocarpus natans.

Plants of the division Bryophyta are divided into three classes.
1. Hepaticae: Liverworts or liver plants are those moss-like plants or gametophytes with liver-shaped leaves.
(i) They are gametophytic plants. The body is thallus in nature.
(ii) Their genitalia are located on the surface of the thallus. Pungdhani is pear shaped and stridhani is flask shaped.
(iii) They are small independent plants. Less than 10 cm in length and 2-20 mm in width.
(iv) They are widespread all over the world. It has 6,000 species in polar, desert and humid regions.
(v) They grow on soil, sand, stone, tree or any object.
A few liverworts- Riccia huebeneriana, Marchantia polymoroha, Asterella californica, Ricciocarpus natans.
2. Anthocerotae: Hornworts are hornworts in which the sexual structure of mosses or gametophytes is horn-shaped.
(i) Their main plants are gametophytes. It is green and flat in structure.
(ii) Their sporophytes are partially self-sustaining.
(iii) They are developed and have columnar capsules.
(iv) Their thallus is heterolateral and recumbent. The genitalia are rooted on the surface of the thallus.
(v) They are found all over the world. Their number of species is 300.
Some hornworts- Anthoceros agrestis, Phaeoceros carolinianus, Ceratophyllum pollination, Folioceros amboinensis, Dendroceros crispus, Notothylas anaporata.
3. Musci
(i) They are known as mosses.
(ii) Their gametophytes are cylindrical or thallus shaped and develop into protonema.
(iii) Their body is more like a stem and the genitalia are formed at the tip of the stem.
(iv) Their sporophytes are divided into pods, setae and capsules.
Examples: Funaria, Sphagnum, Pogonatum.

Plants of the class Bryopsida are called true mosses. They have a ring-like peristome at the mouth of the capsule. 95% of moss plants are true moss. They grow all over the world and have over 12,000 species. Among them, Semibarbula is called carpet moss.
Examples: Semibarbula, Sphagnum, Polytrichum, Funaria etc.